Electric and pneumatic-powered hand power tools such as jacks, hammer drills, air hammer, impact wrenches and reciprocating saws among others, are commonly used in construction and demolition industries, in heavy equipment repair, and in under-ground mining activities. The weights of these types of tools range between 4.5 kg (i.e., 10 lbs) to 22.7 kg (i.e., 50 lbs) and in some cases, e.g., jackhammers, may each 34 kg (i.e., 75 lbs) or more. Such tools typically generate considerable torque and vibratory forces which are transmitted to the operators' hands, arms and bodies making precise manipulation of die tools difficult. Quite often, it is necessary for operators to wield, manipulate, orientate and operate ties tools in three-dimensional work spaces that include multiple outward and upward-directed planes, while the tools are being held at elevations ranging from the waistline to above the shoulders. Extended operation of such tools in these positions may cause muscle fatigue and/or numbness in the operators' bands and arms hereby acting not only operator efficiency, but also their safe handling of the tools. Furthermore, the nature of uses to which such tools are applied often result in the tools being inadvertently jammed, stuck or deflected thereby causing unexpected transmission of torque forces that may cause operators to lose their balance resulting in twisting of their bodies or falls causing injuries.
Multi-component articulating supports for enabling the engagement and manipulation of tools in three-dimensional work spaces are known. Examples include those disclosed in U.S. patent application publication US 2004/0026584 to Libbey et al., published on Feb. 12, 2004; PCT application WO 00/16950 to Casun AB Bygg Och Industriservis, published on Mar. 30, 2000; and European Patent Application 0 192 253 A1 to Construction Robotics, Inc. published on Aug. 27, 1986.
The proximal ends of these types of supports are typically securely and permanently fastened to structural members or platforms that are components of the work spaces or alternatively, awe mounted to transportable platforms, e.g., truck beds or trailers. The distal ends of these supports are provided with tool-engaging devices that securely clamp onto power tools. The tool-engaging devices may be permanently positioned in pre-set orientations, or alternatively, may provide limited movement of the tools in one plane, e.g., a vertical arc or a horizontal arc. Typically, theses types of tool supports are comprised of pluralities of members that are pivotably connected to: (a) each other, (b) to structural elements at the proximal ends of the supports, and (c) to tool-engaging devices at the distal ends of the supports. Most commonly, the first member adjacent the distal end of the support is an articulated arm adapted to move in a vertical plane, and is equipped with a weight-balancing and/or positional control means for a power tool clamped to its distal end. The first member is pivotably connected to a second member whereby the first member can swing in a horizontal arc around its connection point to the second member. The second member is usually pivotably connected to a structural element at the proximal end of the support whereby the second member can swig in limited horizontal arc around its connection point to the structural element. Some articulated supports provide one or more additional members inserted between the first and second member, with each member pivotably connected to its adjacent members thereby enabling each member to swing in a limited horizontal arc around its connection points. Positioning of the tools within three-dimensional workspaces is accomplished by concurrent (a) lateral movements of the members through horizon arcs around their connection points, and (b) vertical movements of the first members adjacent the distal end of the supports.
The known multi-component articulating supports are typically permanently assembled by means of secured pivot shaft connecting adjacent members, most commonly through clevis-type brackets that are integral to the member bodies. The width of the member bodies restricts the horizontal arc movement of adjacent members, i.e., to about 270° or less, so that adjacent members cannot be completely folded against each other. The rugged nature of the tool-engaging devices and their connection to the first members provide only limited operator-controlled positioning and manipulation of hand power tools relative to the first members. Consequently, such supports arm not suitable for use in three-dimensional workspaces where space is restricted or limited and where the tools must be manipulated in multiple radial outward and upward orientations relative to the first member. Another disadvantage is that, due to the permanent assembly of the parts, they can not be easily modified to extend or reduce their scope of movement through disassembly and the addition or removal of one or more members. Furthermore, due to the secure fastenings required to attach the distal ends of the supports to structural members in order to provide stability to the supports when in use, they are not portable, i.e., quickly and easily dismounted form the structural member for transport.
There is a need therefore, to improve the adaptability and maneuverability of multiple-component articulating supports for hand power tools within and throughout restricted three-dimensional workspaces and the portability of such support between jobsites.